Apple Inc. CEO Steve Jobs may have to undergo surgery to remove his pancreas, according to reports quoting doctors.

Jobs had announced a day earlier that he would be on medical leave for the next five months after finding out that his problems are "more complex" than what he thought of them last week.

The idea of Apple without Jobs at the helm is clearly having an impact on the scrip's price, which dropped around 2.3 per cent in Nasdaq trading.

Earlier, Jobs had undergone surgery similar to a Whipple operation involving the removal of parts of his pancreas, bile duct and small intestine, having been diagnosed with a rare type of pancreatic cancer in 2004.

Reports quoted various medical professionals as saying that one of the side effects of this procedure is that the pancreas needed to be removed to prevent a possible pancreatic leak. The patient thereafter has to live with insulin to regulate blood sugar, just as diabetics do. There is also a significant risk of diabetes.

Jobs has handed over the everyday operations of Apple to COO Tim Cook while saying that he will remain involved in "major strategic decisions." The 53-year old said he would retain the helm as CEO while taking a medical leave of absence till the end of June.

Apple had earlier chosen not to provide any details about Jobs health, terming it as a private matter. That has frustrated investors for a while, since Apple's stock plummetted with each pound of weight Jobs lost as he appeared increasingly thin in 2008.

Rumours about his condition also battered the stock value, while Jobs chose to be relatively nonchalant about the issue, calling his treatment "simple and straightforward" till a week ago when he said that the weight loss was on account of a "hormone imbalance".

Apple still declines any further information on the issue of Jobs' health. Jobs co-founded Apple in 1976, and came back to the company in 1997 after having been ousted in the 1980s. He revived the Macintosh computer brand and pushed Apple into new markets with the iPod media player and the iPhone. Reports said that Jobs has not been seen in public since October.

Reports quoted various analysts as lamenting the lack of information from Apple on something that investors are keen to know, going so far as to term it as "not healthy for the business".

Jobs had disclosed in August 2004 that he underwent surgery to remove a tumor related to a rare form of pancreatic cancer that would not require chemotherapy or radiation. At the time, Cook oversaw Apple while Jobs was on a month-long leave.

Fortune magazine reported in March 2008 that Jobs had informed Apple's board about his cancer and the company's directors chose to stay quiet. Reports said that Larry Sonsini, the company's attorney, told directors that Jobs's right to privacy topped disclosure rules, according to Fortune.

However, misinformation about his health has been rife. Jobs appeared visibly thinner when introducing the iPhone 3G at Apple's developers' conference in June 2008, which made investors more concerned about his health. Apple said at the time that he was suffering from a "common bug". With him appearing increasingly frail at company events later in the year, rumours escalated till a month ago when Apple announced that Jobs would not deliver the keynote address at the Macworld conference in San Francisco for the first time in 11 years. A week back, Jobs said he was suffering a hormone imbalance that was the cause of the weight loss, and that the remedy was "relatively simple."

Reports also quoted securities law professor at Columbia Law School John Coffee as saying that the disclosure would "strike many as incomplete," given yesterday's announcement of a five-month long leave of absence. The US Securities and Exchange Commission (SEC) might invetigate whether Steve Jobs or Apple purposely misled investors about his medical condition, and some shareholders may even sue if the stock drops dramatically.

Other reports also said that though Jobs is important to Apple, no one is irreplaceable. They anticipate that while there would be a short-term impact on Apple on account of Jobs' absence, over the longer term things would stablise as there are "a lot of innovative minds at Apple".